1. Field of the Invention
The present invention relates to a plant monitoring apparatus and a plant monitoring method particularly for classifying warnings into each category and displaying the classified warnings.
2. Description of the Related Art
Generally, a plant monitoring apparatus has a function for issuing warnings in a monitoring operation. This warning function provides a mechanism for determining whether warnings are to be issued when a plant monitoring apparatus enters a predetermined state during the operation of a plant, and under the determination, the warnings are notified to operators or so.
As shown in FIG. 6, a known plant monitoring apparatus 11 includes a power generation plant 12, a process measuring unit 13, a warning determining unit 14, a display processing unit 16, and a display unit 17. The process measuring unit 13 measures variables indicating states of the power generation plant 12 to obtain process data. The warning determining unit 14 determines whether a warning is to be issued on the basis of the process data and a predetermined criterion. When the warning is issued, the display processing unit 16 processes warning data into a displayable form, and supplies the data to the display unit 17. The display unit 17, in turn, displays the warning.
The plant monitoring apparatus determines whether the warning is to be issued or not according to changes of state. One of such plant monitoring apparatuses manages information supplied from sensors in an integrated fashion and sets a warning level after determining whether or not the information supplied from the sensors is normal when an error occurs (See Japanese Unexamined Patent Application Publication No. 2002-117468).
In addition, there is an apparatus that allows a user to change the plant warning level information and to store and manage the history of changes in the plant warning level information with an online operation (See Japanese Unexamined Patent Application Publication No. 11-327636).
Unfortunately, such plant monitoring apparatuses notify operators or the like of many warnings, including both critical and insignificant ones, when many warnings are issued. This circumstance is generally called a “flood of warnings”. Accordingly, it is desired to efficiently notify operators of the critical warnings among the flood of warnings.